sync/internal_api/public/read_transaction.h

   1 // Copyright 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef SYNC_INTERNAL_API_PUBLIC_READ_TRANSACTION_H_
   6 #define SYNC_INTERNAL_API_PUBLIC_READ_TRANSACTION_H_
   7
   8 #include "base/compiler_specific.h"
   9 #include "sync/api/attachments/attachment_id.h"
  10 #include "sync/base/sync_export.h"
  11 #include "sync/internal_api/public/base_transaction.h"
  12
  13 namespace tracked_objects {
  14 class Location;
  15 }  // namespace tracked_objects
  16
  17 namespace sync_pb {
  18 class DataTypeContext;
  19 }
  20
  21 namespace syncer {
  22
  23 struct UserShare;
  24
  25 // Sync API's ReadTransaction is a read-only BaseTransaction.  It wraps
  26 // a syncable::ReadTransaction.
  27 class SYNC_EXPORT ReadTransaction : public BaseTransaction {
  28  public:
  29   // Start a new read-only transaction on the specified repository.
  30   ReadTransaction(const tracked_objects::Location& from_here,
  31                   UserShare* share);
  32
  33   // Resume the middle of a transaction. Will not close transaction.
  34   ReadTransaction(UserShare* share, syncable::BaseTransaction* trans);
  35
  36   ~ReadTransaction() override;
  37
  38   // BaseTransaction override.
  39   syncable::BaseTransaction* GetWrappedTrans() const override;
  40
  41   // Return |transaction_version| of |type| stored in sync directory's
  42   // persisted info.
  43   int64 GetModelVersion(ModelType type) const;
  44
  45   // Fills |context| with the datatype context associated with |type|.
  46   void GetDataTypeContext(ModelType type,
  47                           sync_pb::DataTypeContext* context) const;
  48
  49   // Clear |ids| and fill it with the ids of attachments that need to be
  50   // uploaded to the sync server.
  51   void GetAttachmentIdsToUpload(ModelType type, AttachmentIdList* ids) const;
  52
  53   // Return the current (opaque) store birthday.
  54   std::string GetStoreBirthday() const;
  55
  56  private:
  57   void* operator new(size_t size);  // Transaction is meant for stack use only.
  58
  59   // The underlying syncable object which this class wraps.
  60   syncable::BaseTransaction* transaction_;
  61   bool close_transaction_;
  62
  63   DISALLOW_COPY_AND_ASSIGN(ReadTransaction);
  64 };
  65
  66 }  // namespace syncer
  67
  68 #endif  // SYNC_INTERNAL_API_PUBLIC_READ_TRANSACTION_H_